PROJECT SUMMARY (ABSTRACT) There is a fundamental gap in understanding how, in real-world settings, biomechanical and ergonomic fac- tors affect blind cane users? ability to detect drop-offs, obstacles, and texture-related changes in the charac- teristics of the walking surface. This gap is an important problem because, until it is filled, blind individuals, who are generally more prone to falls, will remain exposed to an undue but potentially avoidable risk of falls and a decline in quality of life. Our long-term goal is to improve health outcomes of blind individuals through better long cane design and cane-use biomechanics. The overall objective of this application, which is a logi- cal progression from our previously funded project, is to determine the factors that affect the reliable detection of hazards such as sudden changes in walking-surface texture, drop-offs, and obstacles in real-world settings. Our central hypothesis is that the ergonomic and biomechanical factors identified as significant factors for cane users? detection of drop-offs, obstacles, and sudden walking-surface changes in a laboratory will also be significant factors in real-world settings. The rationale underlying the proposed research is that, with the knowledge obtained from the studies, the real-world applicability of the redesigned, individualized long canes as well as improved, individualized cane-use biomechanics can be demonstrated to blind individuals, orienta- tion and mobility specialists who teach cane skills, and cane manufacturers to enable them to understand and adopt such changes, thus reducing the risk of falls and fall-induced injuries. Guided by the findings of the previous project, the central hypothesis will be tested by pursuing two specific aims: 1) determine the ap- plicability of the laboratory findings from the previous project to drop-off and obstacle detection with the long cane in real-world settings, and 2) determine ergonomic and biomechanical factors involving the long cane that affect the detection of changes in walking-surface texture both in laboratory and real-world settings. Un- der these aims, experimental protocols and psychophysical analysis procedures that were previously estab- lished in the applicant?s laboratory work will be modified to measure the performance of subjects with blind- ness in real-world settings. This proposal?s experimental approach is innovative because we are 1) using a set of prototype cane shafts, cane tips, and a counterweight constructed in accordance with the findings of our previous project, 2) objectively measuring the effect of cane-grasping-arm muscle fatigue on hazard de- tection performance using a portable electromyography system, and 3) capturing the magnitude of applied forces and vibration characteristics resulting from different cane-use biomechanics while the cane is in actual use not only in controlled indoor settings but also in outdoor real-world settings such as sidewalks and park- ing lots. The proposed research is significant because reliable detection and avoidance of hazards on one?s walking path can reduce the incidence of falls, which can lead to lower mortality, a decreased number of emergency room visits and hospital admissions, and an improved quality of life.